Air and fuel supply controlling means for furnaces or the like



I July 31, 1945- H. E. BLAUVELT AIR AND FUEL SUPPLY CONTROLLING MEANSFOR FURNACES OR THE LIKE 2 Sheets-Sheet 1 Filed April 11, 1941 INVENTOR.HOMER t'. BUN/V511 July 31, 1945. H. E. BLAUVELT 2,380,719

AIR AND FUEL SUPPLY CONTROLLING MEANS FOR FURNACES OR THE LIKE FiledApril 11, 1941 2 Sheets-Sheet 2 INVENTOR'. HOMER E. Bun/v51]:

ATTOENEK Patented July S1, 1945- UNITED srrrna;

AIRAND MEANS FOR FURNA Homer E. Blauvelt, Flushing,

Blauveltexecutrix of said Homer E.

deceased CES OR THE LIKE N. Y.; Thelma. It. Blauvelt,

Application April 11, 1941, Serial lilo. 388,033

.6 Claims.

This invention relates generally to air control means for oil burners,gas burners, burners using finely comminuted or powdered combustiblematerial, etc., and more particularly refers to a regulating means forsimultaneous control of pri-" mary air and secondary air supply to theburner.

It is an object of the present invention to provide efllcient primaryair and secondary air supply control means which are automaticallyregulatable according to the combustible load fed to the burner orfurnace.

It is a further object of the present invention to provide simultaneouscontrol of the primary air and secondary air supply to a burner orfurnace, adjustable in accordance with a minimum and amaximumpredetermined rate of fuel supply flow to give substantially perfectcombustion for varying quantities of fuel supply fed to said burner upto said maximum flow.

It isyet another object of the present invention to provide asubstantiallyuniform CO2 con-,

, tent of the flue gases by regulation of the primary and secondary airadmission and the fuel.

A further object of the present invention is to provide in such a burneror furnace the required proportion of primary and secondary air to thecombustible fuel, to give substantially perfect combustion, and tomaintain this proportion irrespective of the amount of fuel consumed.

Another object of the present invention is to provide primary andsecondary air supply operating means for such a humor or furnace whichmeans are accurately and simultaneously controlled for bringing aboutefllcient combustion with maximum CO2 content within the furnace.

In carrying out foregoing objects of the present invention there isprovided a heating system employing a fuel burner apparatus and meansfor-regulating the flow of fuel to said apparatus; with air admissionmeans cooperable with said burner apparatus, rotatable meanscontrollable by said regulating means, and means operable by I saidrotatable means for controlling air supply through said air admissionmeans in accordance with the amount of fuel supplied tofsaid apparatusfor producin a. desired proportion of air to fuel consumed andsubstantially maintaining said proportion during varying rates of flowof said consumed rate of flow thereof. I

This invention accordingly consists in the feafuel up to a.predetermined maximum To enable others skilled in the art so fully tocomprehend the underlying features thereof that they may embody the sameby the modifications in structure and relation contemplated by thisinvention, drawings depicting a. certain form of the invention have beenannexed as a part of this disclosure, and in such drawings, likecharacters of references denote corresponding parts throughout all theviews, of which:

Fig. 1 is a front elevational view of a boiler with mechanism made inaccordance with the invention.

Fig. 2 is a side elevational view partly in section of Fig. 1. e

tures of construction; combination of parts and I in the uniquerelations of the members and in the relative proportioning and as morecompletely outlined herein.

disposition thereof; all

Fig. 3 is a sectional view taken along line 3-3 of Fig. 1 showing thepressure regulator with its connection to the operating shaft connectingthe levers. embodied in the invention.

Fig. 4 is a sectional view taken along line 4-4 of Fig. 1 showing theprimary air inlet and adjustable connection to the operating shaft.

, Fig. 5 is a cross sectional view taken along line 5-5 of Fig. 1 andshowing the adjustable secondary air control and connectionto anoperating shaft. 1

Referring now to the drawings, although there is shown a fire tubeboiler l0, it is understood that any other type, such as a water tubeboiler, locomotive boiler, etc., may be employed, this device forming nopart of the invention.

Boiler I0 is supported by the conventional foundation walls I I formingthe fire box l2 from which the flames F and hot gases enter the firechamber I 3. These flames and hot gases will heat the water l5 aroundthe tubes l4, such flames and hot gases finally reaching the frontchamber I6 and from there passing through the chimney or smoke stack II.All this is conventional and formsno part of the invention.

On the front plate l8 of the boiler is a shaft I9 rotatably mounted inbearings 20, 2|.

' ed upon the front plate 22 of boiler I0 is a thermostat control or arm24 connected by means of a connecting rod 25 and lever 26 to shaft IQfor causing shaft I9 to rotate in accordance with pressure regulator 23,which is determined by the pressure in boiler Ill. V The movement .ofarm 24 'will range within an are up to about sixty degrees to ninetydegrees. The burner apparatus 21 comprises the upright hollow member 28,burner member 29, and fuel line 30. A control valve 3|, which controlsthe flow of fuel to the burner 32 is connected by means of connectingrod 33 and lever 34'to shaft l9.

Mounta pressure regulator 23, having an v the pressure in the Withinhollow member 23 is a butterfly valve or damper 35 which controls theprimary air supply to burner 29 the fuel and air mixture being burnedbelow burner element 32. This opening 31 can be closed by a door 38,which door controls the secondary air supply entering the fire box I 2.Door 38 is controlled from the rotatable shaft l9 by means of an arm 39having an arcuate slot 40 and a sliding member 4| which can be securelyclamped by conventional means within slot 40 at a predetermined positionto be later described. A chain or cable 42 connects sliding member 4| todoor, dam-per or valve 38 of secondary inlet 36. This cable 42 is guidedover the fixed pulleys 43, 44, 45, respectively.

The arm 33 is provided with counterweights as shown at 53 so as toassist in balancing the weight of the damper door 38. The butterflyvalve 35 is controlled from rotatable shaft l3. For this purpose an armor lever 43 is connected to shaft I3,

air supply required for a sixty gallon per hour fuel oil flow, the aboveprocedure is repeated. If at any future time it is desired to run thefurnace with a steam production equivalent to the flow of, sayforty-five gallons of fuel oil'per hour, the clamping members 4|, 52 ofconnecting cable 42 and connecting rod 43, respectively, are clamped inthese positions within the slots 40, 5|, marked for this fuel oilconsumption, thereby repeatedly producing the most efiicient combustionthrough the supplying of the correct amount of primary and secondary airto the fuel burner.

- This arrangement, in other words, will always assaid lever 43 havingan extension 50 provided with an arcuate slot 5|. A member 52 isslidable in slot 5|. An arm 46 connects with butterfly valve 35, saidarm 46 having a counterweight 41 at its free end. Sliding member 52 isprovided with clamping means to secure the sliding member 52 within slot5| at a predetermined position for a purpose later on described.

Referring now more particularly to arms 33 and 49, the curvature of slot5| is determined when the arm 43 is at its lowest position as indicatedat 43, 52' by describing an arc using point 43' as a pivot and rod as aradius. At this time secondary air inlet arm 33 will also be at itslowest position as indicated at 39'. Curvature of slot 4) is determinedby the relation between sliding member 4| within slot 40 and therequired position of the damper door 38, and swinging section 42 ofcable 42 about the surface of pulley 43 when arm 33' is in its saidlowest position. The furnace burner 32 at this time is receiving oilforproducing the lowest practical flame. The

butterfly valve and damper door 38 are now adjusted by hand and securedin their adjusted positions, this position of valve 35 being indicatedby 35:: and the corresponding position of arm 43 by 45a, for the flameto burn the most efllcient way producing a predetermined 00:. Valve 35is secured in its adjusted position by tightening screw 35' and door 33is secured in its adjusted position by means of the knot K of cable 42.Regardless of position of 52 within slot 5| and of 4| within slot 40,the positions of valve 35 and door 38 will always be the same when shaftl9 brings arms 43 and 39 to their lowest positions once the locations ofthe respectivesliding members 4| and 52 have been determined inaccordance with the fuel used and the required primary and secondary airnecessary for complete combustion. The .oil supply to the burner is nowincreased to a flow of, say, eighty gallons per hour, indicating amaximum flame desirable for a particular purpose. The valve 35 and door38 are then again adjusted, this time, however, for an air supply givingthe most eflicient combustion and thereby again a theoretical maximum002. Slots 40 and 5| are now again marked off for positions for highfire, thereby obtaining the graduation marks 52 and 53, respectively.for high fuel consumption. For obtaining graduations' or points betweenthese and low fuel oil flows, for example, to determine the primary andsecondary sure the correct proportion of fuel, primary air and secondaryair, thereby giving the desired predetermined CO2, no matter how muchfuel is being consumed at any particular time between the lowestpractical flame and the maximum predetermined flame.

Operation To start off a cool boiler, more oil will ,be required in thecombustion chamber of the boiler to bring the pressure up as quicklyas pssible. This may require in one particular instance the consumption ofeighty gallons of oil per hour. Assuming that the necessary amount ofpressure has been reached within, say, one hour and onehalf, it will befound'that only sixty gallons of oil per hour are required to maintainthe required steam pressure. The control valve 3| is now set for thisoil flow and clamping members 4| and 52, which at first had been clampedto the proper location for eighty gallons of oil per hour will now bemoved along the slots to the respective indicated graduations on arms 33and 49 for sixty gallons per hour. If a change in oil supply should bedesired these clamping members 4| and 52, respectively controlling theprimary and secondary air supply will be adjusted accordingly.Therefore, if the pressure regulator 23 reacts on the rotating shaft |9on account of the predetermined pressure setting, and pressure regulator23 continuously maintains this pressure, the primary and secondary airsupply to the flre box will be always-such as to provide theproperproportion of air and fuel, thereby producing the most perfectcombustion or, in other words, a substantially theoretical maximum CO2.

It is obvious that. since the oil supply control lever 34, the primaryair supply lever 43 and the secondary air supply lever 39 are allsecured to the common shaft l9, and since the shaft l 9 is rotated bythe action of lever 23 mounted on shaft l9, and further since lever 23is set into motion by the action of pressure regulator 23, that allthese said arms will move and operate their respective mechanismssimultaneously, and in accordance with the predetermined settings.

It is understood that although the invention has been described withreference to oil burners, the aforementioned primary and secondary aircontrol mechanisms may be-employed in connection with furnaces orboilers using other fuels,

such asfor example, natural or illuminating gas,

require or experience suggests without departing from the spirit of theinvention within the scope of the appended claims.

Having thus described the invention what is claimed as new and desiredto be secured by Letters Patent, is:

1. In combination with a heating apparatus having a front plate, a fuelburner and means for supplying fuel to said burner; means forcontrolling the supply of fuel to said burner, said means includingspaced bearings fixed to said plate, a rotatable shaft mounted in saidbearings, means for admitting primary air to said apparatus, means foradmitting secondary air to said apparatus, means for controlling thequantity of primary air to said apparatus, means for controlling thequantity of secondary air to said apparatus; one of said air controllingmeans comprising a member fixed to said shaft mounted in said bearingsto rotate therewith, said member having a curved slot, a valve devicefor one of said air admitting means, an arm connected at one end to saiddevice and having a weight adjacent its other end, a link pivotallyconnected at one end to said arm between said weight and said device,and a member at the other end of said link slidable in said slot; theother of said air controlling means comprising a. member fixed to saidshaft mounted in said bearings to rotate therewith, said last mentionedmember having a curved slot, a movable damper device for the other ofsaid air admitting means, a flexible connection, one end of saidconnection being secured to said last mentioned device, and a memberfixed to the other end of said connection and slidable in said lastmentioned slot.

2. In combination with a heating apparatus having a front plate, a fuelburner and means for supplying fuel to said burner; means forcontrolling the supply of fuel to said burner, said means includingspaced bearings fixed to said plate, a rotatable shaft mounted in saidbearings, means for admitting primary air to said apparatus, means foradmitting secondary air to said apparatus, means for controlling thequantity of primary air to said apparatus, means for controlling thequantity of secondary air to said apparatus; one of said air controllingmeans comprising a member fixed to said shaft to rotate therewith, saidmember having a curved slot, a valve device for one of said airadmitting means, an arm connected at one end to said device and having aweight adjacent its other end, a link pivotally connected at one end tosaid arm between said weight and said device, and a member at the otherend of said link slidable in said slot.

3. In combination with a heating apparatus having a front plate, a fuelburner and means for supplying fuel to said burner; means for con-ntrolling the supply of fuel to said burner, said means including spacedbearings fixed to said plate, a rotatable shaft mounted in saidbearings, means for admitting primary air to said apparatus, means foradmitting secondary air to said apparatus, means for controlling thequantity of primary air to said apparatus, means for controlling thequantity of secondary air to said apparatus, one of said air controllingmeans comprising a member fixed to said shaft, said mem-' her having acurved slot, avalve device for one of said air admitting means, aflexible connection, one end of said connection being secured to saiddevice, and a member fixed to the other end of said connection andslidable in said slot.

4. In combination with a heating apparatus having a front plate, a fuelburner and means for supplying fuel to said burner; means forcontrolling the supply of fuel to said burner, said means includingspaced bearings fixed to said Y plate, a rotatable shaft mounted in saidbearings,

means for admitting primary air to said apparatus, means for admittingsecondary air to said apparatus, means for controlling the quantity ofprimary air to said apparatus, means for controlling the quantity ofsecondary air to said apparatus, one of said air controlling meanscomprising an arm fixed to said shaft to rotate therewith, said armhaving a curved slot, a valve device at one of said air admitting means,and connecting means between said device and said arm, said connectingmeans including a member slidable in said slot; the other of said aircontrolling means comprising a member fixed to said shaft, said lattermember having a curved slot, a valve device at the other of said airadmitting :means, a connection having one end secured to said lattermentioned device and its other end secured in the said last mentionedslot.

5. In combination with a heating apparatus having a front plate, a fuelburner and means for supplying fuel to saidburner; means for controllingthe supply of fuel to said burner, said means including spaced bearingsfixed to said plate, a rotatable shaft mounted in said bearings, meansfor admitting primary air to said apparatus, means for admittingsecondary air to said apparatusmeans for controlling the quantity ofprimary air to said apparatus, means for controlling the quantity ofsecondary air to said apparatus; each of said air controlling meanscomprising a movable damper tive air admitting mea an arm fixed to saidshaft to rotate therewith, said arm having a curved slot, and meansconnecting each of said damper devices with said arm, said connectingmeans having a part slidable in said slot.

6. In combination with a heating apparatus having a front plate, a fuelburner and means for supplying fuel to said burner; means forcontrolling the supply of fuel to said burner, said means includingspaced bearings fixed to said plate, a rotatable shaft mounted in saidbearings, means for admitting primary air to said apparatus, means foradmitting secondary air to said apparatus, means for controlling thequantity of primary air to said apparatus, means for controlling theamount of secondary air to said apparatus; each of said air controllingmeans comprising a movable damper device at the respective air admittingmeans, an arm fixed to said shaft to rotate therewith, said arm having acurved slot, and means connecting said device HOMER E. BLAU'VELT,

device for the respec-

